Hi Joshua, On 15.12.2011, at 19:33, Joshua Ball wrote:
> Hi, > > The following program crashes with the following error: > > ** ERROR **: gtk2hs_value_as_haskellobj: unable to handle GValue > with type GParam > please report this as a bug to gtk2hs-devel@lists.sourceforge.net > Trace/breakpoint trap > > > module Main where > > import Graphics.UI.Gtk > > main = do > initGUI > window <- windowNew > cb <- comboBoxNewText > comboBoxAppendText cb "one" > comboBoxAppendText cb "two" > on cb popupShownNotify $ putStrLn "popupShownNotify" > containerAdd window cb > widgetShow cb > widgetShow window > mainGUI > > I'm using GHC version 7.2.1. I filed a bug at > http://hackage.haskell.org/trac/gtk2hs/ticket/1243 > , but it looks like that tracker doesn't get much love. > Yes, the bug tracker is not something I consult on daily basis. I've investigated and it turned out that the signal was incorrectly connected, so it never worked. In order to fix this, I've generalized the whole approach: the signal above was listening for a property change, it wasn't a normal signal. So I added a new meta-signal handler in gtk/.../Object called notifyProperty that you simply pass an Attribute for which you want to be notified when it changes. Not every Attribute is a Property, but it works with many common ones, for instance, with the comboBoxPopupShown attribute. So your example now looks like this: module Main where import Graphics.UI.Gtk import Control.Monad.Trans main = do initGUI window <- windowNew cb <- comboBoxNewText comboBoxAppendText cb "one" comboBoxAppendText cb "two" comboBoxSetActive cb 0 on cb (notifyProperty comboBoxPopupShown) $ putStrLn ("popupShownNotify") containerAdd window cb widgetShow cb widgetShow window on window deleteEvent $ liftIO mainQuit >> return True mainGUI The fix is in darcs. Cheers, Axel > Josh "Ua" Ball > > -- > Borrow my books: http://goo.gl/UBbSH > ------------------------------------------------------------------------------ > 10 Tips for Better Server Consolidation > Server virtualization is being driven by many needs. > But none more important than the need to reduce IT complexity > while improving strategic productivity. Learn More! > http://www.accelacomm.com/jaw/sdnl/114/51507609/_______________________________________________ > Gtk2hs-devel mailing list > Gtk2hs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/gtk2hs-devel ------------------------------------------------------------------------------ Learn Windows Azure Live! Tuesday, Dec 13, 2011 Microsoft is holding a special Learn Windows Azure training event for developers. It will provide a great way to learn Windows Azure and what it provides. You can attend the event by watching it streamed LIVE online. Learn more at http://p.sf.net/sfu/ms-windowsazure _______________________________________________ Gtk2hs-devel mailing list Gtk2hs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gtk2hs-devel
